Vanadium dioxide thin films have been grown from vanadium tetrakis
(t-butoxide) by the sol-gel process. A new method for the synthesis of
the vanadium precursor was also developed. Films were deposited by
dipcoating glass slides from an isopropanol solution, followed by postdeposition
annealing of the films at 600°C under nitrogen. The
properties of these films, to a high degree, were a function of
crystalline boundaries and crystalline grain size. These gel-derived
V02 films undergo a reversible semiconductor-to-metal phase transition
near 72°C, exhibiting characteristic resistive and spectral switching
comparable with near stoichiometric V02 films prepared on non-
crystalline substrates by other techniques. Paralleling the
investigation of pure V02, films were doped with hexavalent transition
metal oxides to demonstrate lowering of the transition of the transition
temperature.
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